<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>index</title>
</head>
<body>
<script type="text/javascript">
let pFn = new Promise( (resolve,reject) => {
  setTimeout(() => {
    let data = 1
    if(data){
      resolve('成功：我是promise中resolve的结果')
    }else{
      reject('失败：我是promise中reject的结果')
    }
  },7000)
})
console.log('准备调用promise')
pFn.then( value => {
  console.warn(value)
}).catch((err)=>{
  console.error(err)
})
console.log('调用promise结束')

function loadNum(num,time){
  let numRes = new Promise((resolve,reject) => {
  setTimeout(() => {
    if(num > 0){
      resolve('all：我是promise.all中resolve的结果')
    }else{
      reject('all：我是promise.all中reject的结果')
    }
  },time)
  })
  return numRes
}
console.log('调用promise.all开始')
let allDone = Promise.all([loadNum(2,2000),loadNum(0,5000)])
allDone.then(res => {
  console.log(res)
}).catch(error=>{
  console.error(error)
})
console.log('调用promise.all结束')

new Promise((resolve,reject) => {
  resolve()
}).then(
  ()=>{
    console.log(1)
  },
  ()=>{
    console.log(2)
  }
).then(
  ()=>{
    console.log(3)
  },
  ()=>{
    console.log(4)
  }
)
</script>
</body>
</html>